flac-opt (free lossless audio codec)

flac is open source software that can reduce the amount of storage
space needed to store digital audio signals without needing to remove
information in doing so. This version of flac is newer than the one
included in Slackware, and is installed in /opt/flac-opt so it won't
conflict with Slackware's flac package.

The main reason for using this is that this newer version of flac
supports multithreaded encoding (via the -j option), which speeds up
the process dramatically. Even without using -j, encodes about 25%
faster than Slackware's flac.

Decoding speed is the same (and can't use multiple threads), so
recompiling e.g. media player apps to use this version of flac doesn't
make sense.

After the package is installed, either log out & back in, or run
"source /etc/profile.d/flac-opt.sh" to put the new flac and metaflac
commands in your PATH. flac-opt.sh is installed +x by default.

SlackBuild developers: if you're writing a SlackBuild that needs the
flac libraries in this package, put this somewhere near the top of
your build script (after the "set -e"):

   source /etc/profile.d/flac-opt-dev.sh

The -dev file is not installed executable, to avoid conflicting with
the standard flac libraries. It can also be sourced in an interactive
shell, if needed, but DO NOT "chmod +x" this file.

By default, flac-opt is built with assembly language optimizations. If
you get "illegal instruction" errors at runtime, rebuild the package
with ASM=no in the environment. This should only happen on elderly
(first-generation) x86_64 hardware, such as the original Athlon64.

By default, flac-opt is built with upstream's default C optimization,
which is -O3. There's no reason this should bother anyone... but if it
does, you can built with FORCE_O2=yes in the environment.